class Emacs < Formula
  desc "GNU Emacs text editor"
  homepage "https://www.gnu.org/software/emacs/"
  url "https://ftp.gnu.org/gnu/emacs/emacs-26.3.tar.xz"
  mirror "https://ftpmirror.gnu.org/emacs/emacs-26.3.tar.xz"
  sha256 "4d90e6751ad8967822c6e092db07466b9d383ef1653feb2f95c93e7de66d3485"

  bottle do
    sha256 "9ab33f4386ca5f7326a8c28da1324556ec990f682a7ca88641203da0b42dbdae" => :catalina
    sha256 "8162a26246de7db44c53ea0d0ef0a806140318d19c69e8e5e33aa88ce7e823a8" => :mojave
    sha256 "6a2629b6deddf99f81abb1990ecd6c87f0242a0eecbb6b6c2e4c3540e421d4c4" => :high_sierra
    sha256 "2a47477e71766d7dd6b16c29ad5ba71817ed80d06212e3261ef3c776e7e9f5a2" => :sierra
  end

  head do
    url "https://github.com/emacs-mirror/emacs.git"

    depends_on "autoconf" => :build
    depends_on "gnu-sed" => :build
    depends_on "texinfo" => :build
  end

  depends_on "pkg-config" => :build
  depends_on "gnutls"

  def install
    args = %W[
      --disable-dependency-tracking
      --disable-silent-rules
      --enable-locallisppath=#{HOMEBREW_PREFIX}/share/emacs/site-lisp
      --infodir=#{info}/emacs
      --prefix=#{prefix}
      --with-gnutls
      --without-x
      --with-xml2
      --without-dbus
      --with-modules
      --without-ns
      --without-imagemagick
    ]

    if build.head?
      ENV.prepend_path "PATH", Formula["gnu-sed"].opt_libexec/"gnubin"
      system "./autogen.sh"
    end

    system "./configure", *args
    system "make"
    system "make", "install"

    # Follow MacPorts and don't install ctags from Emacs. This allows Vim
    # and Emacs and ctags to play together without violence.
    (bin/"ctags").unlink
    (man1/"ctags.1.gz").unlink
  end

  plist_options :manual => "emacs"

  def plist; <<~EOS
    <?xml version="1.0" encoding="UTF-8"?>
    <!DOCTYPE plist PUBLIC "-//Apple//DTD PLIST 1.0//EN" "http://www.apple.com/DTDs/PropertyList-1.0.dtd">
    <plist version="1.0">
    <dict>
      <key>KeepAlive</key>
      <true/>
      <key>Label</key>
      <string>#{plist_name}</string>
      <key>ProgramArguments</key>
      <array>
        <string>#{opt_bin}/emacs</string>
        <string>--fg-daemon</string>
      </array>
      <key>RunAtLoad</key>
      <true/>
    </dict>
    </plist>
  EOS
  end

  test do
    assert_equal "4", shell_output("#{bin}/emacs --batch --eval=\"(print (+ 2 2))\"").strip
  end
end